Renewables could meet 80 percent of all energy needs by 2050, says IPCC

Posted: 10 May 2011

Close to 80 percent of the world‘s energy supply could be met by renewables by mid-century if backed by the right enabling public policies a new report shows.

The findings, from over 120 researchers working with the Intergovernmental Panel on Climate Change (IPCC), also indicate that the growing use of renewable energy could lead to cumulative greenhouse gas savings equivalent to 220 to 560 Gigatonnes of carbon dioxide between 2010 and 2050.

The upper end of the scenarios assessed, representing a cut of around a third in greenhouse gas emissions from business-as-usual projections, could assist in keeping concentrations of greenhouse gases at 450 parts per million.

It could also help to hold the increase in global temperature below 2 degrees Celsius – an aim recognized in the United Nations Climate Convention's Cancun Agreements.

The findings, approved by member countries of the IPCC meeting in Abu Dhabi, United Arab Emirates, are a summary for policy-makers,  of a comprehensive assessment compiled by over 120 leading experts.

Geothermal power station, Fang, Thailand
Geothermal power station, Fang, Thailand. Photo © 2000 Geothermal Education Office

Ramon Pichs, Co-Chair of the IPCC's Working Group III, that oversaw the report, said it showed that it is was not resources but public policies that will either expand or constrain renewable energy development over the coming decades. Developing countries had an important stake in this future — this is where most of the 1.4 billion people without access to electricity live yet also where some of the best conditions exist for renewable energy deployment.

Four scenarios

The six renewable energy technologies reviewed are:

  • Bioenergy, including energy crops; forest, agricultural and livestock residues and so called second generation biofuel
  • Direct solar energy including photovoltaics and concentrating solar power
  • Geothermal energy, based on heat extraction from the Earth‘s interior
  • Hydropower, including run-of-river, in-stream or dam projects with reservoirs
  • Ocean energy, ranging from barrages to ocean currents and ones which harness temperature differences in the marine realm
  • Wind energy, including on and offshore systems .

The most optimistic of four scenarios set out in the report projects that renewable energy could account for as much as 77 percent of the world‘s energy demand by 2050, amounting to about 314 of 407 Exajoules per year. This is over three times the annual energy supply in the United States in 2005, or a similar level of supply on the Continent of Europe.

Seventy percent is up from just under 13 percent of the total primary energy supply of around 490 Exajoules in 2008. Each of the scenarios is underpinned by a range of variables such as changes in energy efficiency, population growth and per capita consumption. These lead to varying levels of total primary energy supply in 2050, with the lowest of the four scenarios seeing renewable energy accounting for a share of 15 percent in 2050, based on a total primary energy supply of 749 Exajoules.

Declining costs

While the report concludes that the proportion of renewable energy will probably increase even without enabling policies, past experience has shown that the largest increases come with concerted policy efforts.

ocean turbine farm
Illustration of a massive ocean turbine farm. Credit: Voice of America

Though in some cases renewable energy technologies are already economically competitive, the production costs are currently often higher than market energy prices. However, if environmental impacts such as emissions of pollutants and greenhouse gases were monetized and included in energy prices, more renewable energy technologies may become economically attractive.

For most of them, costs have declined over the last decades and the authors expect significant technical advancements and further cost reductions in the future, resulting in a greater potential for climate change mitigation.

Public policies that recognize and reflect the wider economic, social and environmental benefits of renewable energies, including their potential to cut air pollution and improve public health, will be key for meeting the highest renewables deployment scenarios.

Increasing the share of renewables requires additional short-term and long-term integration efforts,the report says. Studies clearly show that combining different variable renewable sources, and resources from larger geographical areas, will be beneficial in smoothing the variability and decreasing overall uncertainty for the power system.

Key findings

  • Of the around 300 Gigawatts (GW) of new electricity generating capacity added globally between 2008 and 2009, 140 GW came from renewable energy.
  • Despite global financial challenges, renewable energy capacity grew in 2009—wind by over 30 percent; hydropower by three percent; grid-connected photovoltaics by over 50 percent; geothermal by 4 percent; solar water/heating by over 20 percent and ethanol and biodiesel production rose by 10 percent and 9 percent respectively.
  • Developing countries host more than 50 percent of current global renewable energy capacity.
  • Most of the reviewed scenarios estimate that renewables will contribute more to a low carbon energy supply by 2050 than nuclear power or fossil fuels using carbon capture and storage (CCS).
  • The technical potential of renewable energy technologies exceeds the current global energy demand by a considerable amount — globally and in respect of most regions of the world.
  • Under the scenarios analyzed in-depth, less than 2.5 percent of the globally available technical potential for renewables is used — in other words over 97 percent is untapped underlining that availability of renewable source will not be a limiting factor.
  • Accelerating the deployment of renewable energies will present new technological and institutional challenges, in particular integrating them into existing energy supply systems and end use sectors.
  • According to the four scenarios analyzed in detail, the decadal global investments in the renewable power sector range from 1,360 to 5,100 billion US dollars to 2020 and 1,490 to 7,180 billion US dollars for the decade 2021 to 2030. For the lower values, the average yearly investments are smaller than the renewable power sector investments reported for 2009.
  • A combination of targeted public policies allied to research and development investments could reduce fuel and financing costs leading to lower additional costs for renewable energy technologies.
  • Public policymakers could draw on a range of existing experience in order to design and implement the most effective enabling policies - there is no one-size-fits-all policy for encouraging renewables.